本文意在說明杜詩學的研究並非對單一批評作品的分析，而是各時代不同作品間的流動關係，文學批評亦存在互文性的可能。在杜詩學史上，看似孤立的作品，其觀念、方法與內容、形式等，往往與前行作品有著相當密切的互文關係。本論文探討明代儒者張綖的杜詩學，考證其三部著作間的關係，以及他對元代杜詩學的因承問題。並分析其杜詩詮釋的方法與特色，實乃承自張性《杜律演義》而來，其追求本義，卻反而因時代與個人侷限而失卻真旨，皆反映了他詮釋杜詩的不足之處。因此本文進而思考在杜詩學史上，論詩者雖有自覺，但仍一再陷於附會論詩的問題，是知杜詩中的倫常特性，並非以呆板的附會所能體現，而是存在於讀者意識中。

Historically, students of Du Fu’s poetry have tended to treat each poem in isolation; however, as can be observed from critical studies of their ideas, method and form, Du Fu’s poems are often closely related to one another. This article examines the Ming dynasty Confucian Zhang Yan’s 張綖 studies of Du Fu’s poetry in order to discern the relation between his three works on the subject as well as determine the influence of Yuan dynasty studies on his views. In addition, this article analyzes Zhang Yan’s interpretation of the characteristics and methods found in Du Fu’s poetry. It is argued here that while Zhang Yan succeeded in advancing the study of Du Fu’s poems, he also proposed some preposterous and inadequate theories. On the basis of this observation, the article proceeds to consider the dilemmas encountered by Du Fu’s critics through the ages, and the delicate relationship between such dilemmas and classical poetry.